1. Field of the Invention
The present invention relates to a mark arrangement inspecting method for inspecting whether a mark such as an alignment mark or a measurement mark is arranged on mask data in accordance with a predetermined rule. Moreover, the present invention relates also to mask data that is inspected by the mark arrangement inspecting method. Furthermore, the present invention relates also to a manufacturing method of a semiconductor device that is manufactured by using the mark generated based on the mask data that is inspected by the mark arrangement inspecting method.
2. Description of the Related Art
In manufacturing a semiconductor device, a pattern is formed by a photomask in a predetermined area for each process such as introduction of impurities, formation of a contact hole/via hole, and formation of a wiring pattern to perform the process. At this time, an alignment mark for positioning for ensuring a relative position between respective processes and a measurement mark for inspecting a displacement or a process result are arranged on scribe lines of a photomask.
Conventionally, photomask data is generated by using a computer-aided design (CAD) in the following manner (for example, see Japanese Patent Application Laid-open No. 2004-157518). First, a design technology such as a design rule conforming to a device, an operational frequency, and the like to be used and a suitable process technology are determined, and thereafter, logical design, layout design, and design verification are performed, whereby chip data of a semiconductor device part is generated. Then, after the layout design of the semiconductor device is completed, a chip size, the number of impositions on the photomask, and the like are determined, and type information is determined, the alignment mark and the measurement mark conforming to a mark specification necessary for each process technology or each manufacturing equipment are generated, and an arrangement process of the alignment mark and the measurement mark on scribe lines including the verification of a positional relationship between photomasks used in pre- and post-processing is performed, whereby scribe line data is formed.
The number of the alignment marks and the measurement marks arranged on the scribe lines in this manner is as many as 1500 or more per product. Moreover, some alignment marks and measurement marks depend on a notch direction of a semiconductor wafer or a direction of a word line in a semiconductor cell formed on the semiconductor wafer. In other words, the arrangement direction of some alignment marks and measurement marks are determined in a predetermined direction. Therefore, conventionally, after designing the scribe line data, the alignment marks and the measurement marks are visually checked. However, there arises a problem that incorrect arrangement of the alignment marks and the measurement marks is missed with high possibility because, for example, the number of the alignment marks and the measurement marks as a check target is large and it is difficult to visually find an error. Moreover, human resources for the visual inspection cannot be ignored. Furthermore, once the arrangement error of the alignment mark is missed, a mask with which exposure and inspection cannot be performed is manufactured and a mask may need to be refined (reproduced) in the worst case, which adversely affects the turn-around time (TAT) and the manufacturing cost of the semiconductor device.